Chip-firing via open covers

Algebra Seminar
Monday, August 26, 2013 - 3:00pm for 1 hour (actually 50 minutes)
Skiles 005
Spencer Backman – Georgia Institute of Technology –
Madhusudan Manjunath
Chip-firing on graphs is a simple process with suprising connections to various areas of mathematics. In recent years it has been recognized as a combinatorial language for describing linear equivalence of divisors on graphs and tropical curves. There are two distinct chip-firing games: the unconstrained chip-firing game of Baker and Norine and the Abelian sandpile model of Bak, Tang, and Weisenfled, which are related by a duality very close to Riemann-Roch theory. In this talk we introduce generalized chip-firing dynamics via open covers which provide a fine interpolation between these two previously studied models.